八年级上练习题7

北师⼤版⼋年级上册数学第七章⼆元⼀次⽅程组练习题（带解析）北师⼤版⼋年级上册数学第七章⼆元⼀次⽅程组练习题（带解析）考试范围：xxx ；考试时间：100分钟；命题⼈：xxx1. 答题前填写好⾃⼰的姓名、班级、考号等信息2. 请将答案正确填写在答题卡上分卷I分卷I 注释⼀、单选题(注释)1、甲⼄两地相距360千⽶，⼀轮船往返于甲、⼄两地之间，顺⽔⾏船⽤18⼩时，逆⽔⾏船⽤24⼩时，若设船在静⽔中的速度为x 千⽶/时，⽔流速度为y 千⽶/时，则下列⽅程组中正确的是（） A ．B ．C ．D ．2、已知有含盐20%与含盐5%的盐⽔，若配制含盐14%的盐⽔200千克，设需含盐20%的盐⽔x 千克，含盐5%的盐⽔y 千克，则下列⽅程组中正确的是（） A ．B ．C ．D ．3、如果⼀个两位数的⼗位数字与个位数字之和为6，那么这样的两位数的个数是（） A ．3 B ．6 C ．5 D ．44、已知x b+5y 3a 和－3x 2a y 2－4b是同类项，那么a,b 的值是（）5、如果5x3m－2n－2y n－m+11=0是⼆元⼀次⽅程，则（）A．m=1,n=2 B．m=2,n=1 C．m=－1,n=2 D．m=3,n=46、⽤加减法解⽅程组时，要使两个⽅程中同⼀未知数的系数相等或相反，有以下四种变形的结果：①②③④其中变形正确的是（）A．①②B．③④C．①③D．②④7、⽤代⼊法解⽅程组使得代⼊后化简⽐较容易的变形是（）A．由①得x=B．由①得y=C．由②得x=D．由②得y=2x－58、四名学⽣解⼆元⼀次⽅程组提出四种不同的解法，其中解法不正确的是（）A．由①得x=，代⼊②B．由①得y=，代⼊②C．由②得y=－，代⼊①D．由②得x=3+2y，代⼊①9、已知⽅程mx+(m+1)y=4m－1是关于x,y的⼆元⼀次⽅程，则m的取值范围是（）A．m≠0B．m≠－1 C．m≠0且m≠1D．m≠0且m≠－110、⼆元⼀次⽅程3a+b=9在正整数范围内的解的个数是（）A．0 B．1 C．2 D．3更多功能介绍/doc/be631667312b3169a451a4e8.html /zt/11、如图，10块相同的长⽅形墙砖拼成⼀个矩形，设长⽅形墙砖的长和宽分别为x厘⽶和y厘⽶，则依题意列⽅程组正确的是A ．B ．C ．D ．12、某车间有56名⼯⼈，每⼈每天能⽣产螺栓16个或螺母24个，设有x 名⼯⼈⽣产螺栓，y 名⼯⼈⽣产螺母，每天⽣产的螺栓和螺母按1：2配套，下⾯所列⽅程组正确的是（） A ．B ．C ．D ．13、已知⽅程组中x ，y 的互为相反数，则m 的值为（）A ．2B ．﹣2C ．0D ．414、下列⽅程是⼆元⼀次⽅程的是（） A ．B ．C ．3x ﹣8y=11D ．7x+2=15、关于x 、y 的⼆元⼀次⽅程组的解满⾜不等式＞0，则的取值范围是（） A ．＜-1 B ．＜1 C ．＞-1 D ．＞116、⽅程组的解是（）A ．B ．C ．D ．由于疏忽，表格中捐款40元和50元的⼈数忘记填写了，若设捐款40元的有x 名同学，捐款50元的有y 名同学，根据题意，可得⽅程组（）A. B.C. D.18、将⽅程中的x的系数化为整数，则下列结果正确的是（）A．B．C．D．19、雅安地震后，灾区急需帐篷．某企业急灾区之所急，准备捐助甲、⼄两种型号的帐篷共1500顶，其中甲种帐篷每顶安置6⼈，⼄种帐篷每顶安置4⼈，共安置8000⼈．设该企业捐助甲种帐篷x顶、⼄种帐篷y顶，那么下⾯列出的⽅程组中正确的是A．B．C．D．20、若|3x+y+5|+|2x－2y－2|=0，则2x2－3xy的值是（）A．14 B．－4 C．－12 D．12分卷II分卷II 注释⼆、填空题(注释)21、⽅程组的解是．22、在⽅程组中，若x ＞0，y ＜0，则m 的取值范围是．23、已知⽅程组的解为，则2a ﹣3b 的值为．24、若（x+y+4）2+|3x ﹣y|=0，则x= ，y= ．25、已知⼆元⼀次⽅程2x+3y+1=0，⽤含x 的代数式表⽰y ，则y= ．26、请写出⼀个以x ，y 为未知数的⼆元⼀次⽅程组，要求满⾜下列条件：①由两个⼆元⼀次⽅程组成；②⽅程组的解为，这样的⽅程组是．27、⼀次数学测试，满分为100分．测试分数出来后，同桌的李华和吴珊同学把他俩的分数进⾏计算，李华说：我俩分数的和是160分，吴珊说：我俩分数的差是60分．那么对于下列两个命题：①俩⼈的说法都是正确的，②⾄少有⼀⼈说错了．真命题是（填写序号）．28、请写出⼀个以x ，y 为未知数的⼆元⼀次⽅程组，且同时满⾜下列两个条件：①由两个⼆元⼀次⽅程组成；②⽅程组的解为，这样的⽅程组可以是____________．按此规律，第n 个⽅程组为___________，它的解为___________（n 为正整数）.30、⽅程组的解是_____________.三、计算题(注释)31、解⽅程组：．32、解⽅程组：（1）（2）33、解⽅程组：（1）（2）34、解⽅程组：35、若是⼆元⼀次⽅程ax －by=8和ax+2by=－4的公共解，求2a －b 的值．36、解下列⽅程：（1）．（2）（3）（4）37、解⽅程组38、解⽅程组（5分）（1）39、解下列⼆元⼀次⽅程组（1） (2)40、（1）计算：（2）解⽅程组：四、解答题(注释)41、端午节期间，某校“慈善⼩组”筹集到1240元善款，全部⽤于购买⽔果和粽⼦，然后到福利院送给⽼⼈，决定购买⼤枣粽⼦和普通粽⼦共20盒，剩下的钱⽤于购买⽔果，要求购买⽔果的钱数不少于180元但不超过240元．已知⼤枣粽⼦⽐普通粽⼦每盒贵15元，若⽤300元恰好可以买到2盒⼤枣粽⼦和4盒普通粽⼦．（1）请求出两种⼝味的粽⼦每盒的价格；（2）设买⼤枣粽⼦x 盒，买⽔果共⽤了w 元．①请求出w 关于x 的函数关系式；②求出购买两种粽⼦的可能⽅案，并说明哪⼀种⽅案使购买⽔果的钱数最多．42、某农户原有15头⼤⽜和5头⼩⽜，每天约⽤饲料325kg ；两周后，由于经济效益好，该农户决定扩⼤养⽜规模，⼜购进了10头⼤⽜和5头⼩⽜，这时每天约⽤饲料550kg ．问每头⼤⽜和每头⼩⽜1天各需多少饲料？ 43、某种仪器由1种A 部件和1个B 部件配套构成．每个⼯⼈每天可以加⼯A 部件1000个或者加⼯B 部件600个，现有⼯⼈16名，应怎样安排⼈⼒，才能使每天⽣产的A 部件和B 部件配套？44、某班到毕业时共结余经费1800元，班委会决定拿出不少于270元但不超过300元的资⾦为⽼师购买纪念品，其余资⾦⽤于在毕业晚会上给50位同学每⼈购买⼀件⽂化衫或⼀本相册作为纪念．已知每件⽂化衫⽐每本相册贵9元，⽤200元恰好可以买到2件⽂件衫和5本相册．（1）求每件⽂化衫和每本相册的价格分别为多少元？（2）有⼏种购买⽂化衫和相册的⽅案？哪种⽅案⽤于购买⽼师纪念品的资⾦更充⾜？45、解⽅程（组）（1）（2）．46、某学校初⼆级甲、⼄两班共有学⽣150⼈，他们的期末考试数学平均分为64.4分，若甲班学⽣平均分为72分，⼄班学⽣平均分为57分，那么甲、⼄两班各有学⽣多少⼈？47、⼀辆汽车从A地驶往B地，前路段为普通公路，其余路段为⾼速公路．已知汽车在普通公路上⾏驶的速度为60km/h，在⾼速公路上⾏驶的速度为100km/h，汽车从A 地到B地⼀共⾏驶了2.2h．请你根据以上信息，就该汽车⾏驶的“路程”或“时间”，提出⼀个⽤⼆元⼀次⽅程组解决的问题，并写出解答过程．48、解⽅程组．49、⼩⽂在甲、⼄两家超市发现他看中的篮球的单价相同，书包单价也相同，⼀个篮球和三个书包的总费⽤是400元.两个篮球和⼀个书包的总费⽤也是400元.（1）求⼩⽂看中的篮球和书包单价各是多少元？（2）某⼀天⼩⽂上街，恰好赶上商家促销，超市甲所有商品打九折销售，超市⼄全场购物满100元返30元购物券（不⾜100元不返券，购物券全场通⽤），如果他只能在同⼀家超市购买他看中的篮球和书包各⼀个，应选择哪⼀家超市购买更省钱？50、解⽅程组：试卷答案1.【解析】试题分析：根据等量关系：顺⽔⾏船⽤18⼩时，逆⽔⾏船⽤24⼩时，即可列出⽅程组. 由题意可列⽅程组为，故选A.考点：本题考查的是根据实际问题列⽅程组点评：解题关键是要读懂题⽬的意思，根据题⽬给出的条件，找出合适的等量关系，列出⽅程组．2.【解析】试题分析：根据等量关系：盐⽔总质量为200千克，配制前后的含盐量相同，即可列出⽅程组.由题意可列⽅程组为，故选C.考点：本题考查的是根据实际问题列⽅程组点评：解题关键是要读懂题⽬的意思，根据题⽬给出的条件，找出合适的等量关系，列出⽅程组．3.【解析】试题分析：可以设两位数的个位数为x，⼗位为y，根据两数之和为6，且xy为整数，分别讨论两未知数的取值即可．注意不要漏解．设两位数的个位数为x，⼗位为y，根据题意得：x+y=6，∵xy都是整数，∴当x=0时，y=6，两位数为60；当x=1时，y=5，两位数为51；当x=2时，y=4，两位数为42；当x=3时，y=3，两位数为33；当x=4时，y=2，两位数为24；当x=5时，y=1，两位数为15；则此两位数可以为：60、51、42、33、24、15，共6个，故选B．考点：本题考查了⼆元⼀次⽅程的应⽤点评：解题的关键在于根据未知数的整数性质讨论未知数的具体值，注意不要漏掉两位数的个位数可以为0的情况．4.【解析】试题分析：根据同类项的定义即可得到关于a、b的⽅程组，解出即可.由题意得，解得，故选D.考点：本题考查的是同类项点评：解答本题的关键是熟记同类项的定义：所含有的字母相同，并且相同字母的指数也相同的项叫同类项.5.【解析】试题分析：根据⼆元⼀次⽅程的定义即可得到关于m、n的⽅程组，解出即可.由题意得，解得，故选D.考点：本题考查的是⼆元⼀次⽅程的定义点评：解答本题的关键是熟练掌握⼆元⼀次⽅程必须符合以下三个条件：（1）⽅程中只含有2个未知数；（2）含未知数项的最⾼次数为⼀次；（3）⽅程是整式⽅程．注意：π是⼀个数．6.【解析】试题分析：根据等式的基本性质把⽅程组中的每个⽅程分别变形，注意不能漏乘项．（1）第⼀个⽅程右边的1漏乘了3，第⼆个⽅程右边的8漏乘了2，故变形不正确；（2）第⼀个⽅程右边的1漏乘了2，第⼆个⽅程右边的8漏乘了3，故变形不正确；（3）是利⽤等式的性质把x的系数化为了互为相反数的数，变形正确；（4）是利⽤等式的性质把y的系数化为了互为相反数的数，变形正确．故选B．考点：本题考查的是解⼆元⼀次⽅程组点评：解答本题的关键是注意⽅程组中，两个⽅程中同⼀未知数的系数相等或互为相反数时，直接运⽤加减法求解．7.【解析】试题分析：⽤代⼊法解⽅程组的第⼀步：尽量⽤其中⼀个未知数表⽰系数较简便的另⼀个未知数．A、B、C、D四个答案都是正确的，但“化简⽐较容易的”只有D．故选D.考点：本题考查的是代⼊法解⼆元⼀次⽅程组点评：解答本题的关键是注意在⽤其中⼀个未知数表⽰另⼀个未知数时，尽量避免出现分数．8.【解析】试题分析：此题中四位同学均利⽤了代⼊法求⽅程组的解，需对四个答案进⾏逐⼀分析求解．A、B、D均符合等式的性质，不符合题意；C、应该由②得y=，故错误，符合题意.考点：本题考查的是代⼊法解⼆元⼀次⽅程组点评：解答本题的关键是熟练掌握代⼊法解⼆元⼀次⽅程组，同时注意⽅程在进⾏合理变形时要根据等式的性质．9.【解析】试题分析：根据⼆元⼀次⽅程的定义即可得到结果.由题意得m≠0且m+1≠0，解得m≠0且m≠－1，故选D.考点：本题考查的是⼆元⼀次⽅程的定义点评：解答本题的关键是熟练掌握⼆元⼀次⽅程必须符合以下三个条件：（1）⽅程中只含有2个未知数；（2）含未知数项的最⾼次数为⼀次；（3）⽅程是整式⽅程．注意：π是⼀个数．10.【解析】试题分析：根据题意，⼆元⼀次⽅程3a+b=9的解为正整数，分类讨论、解答出即可．根据题意，a ，b 为正整数，∴当a=1时，b=9-3=6，当a=2时，b=9-6=3，当a=3时，b=0，不符合题意，所以，⽅程在正整数范围内的解的个数是2个故选C.考点：本题主要考查了解⼆元⼀次⽅程点评：采⽤“给⼀个，求⼀个”的⽅法，即先给出其中⼀个未知数的值，再依次求出另⼀个的对应值． 11.【解析】试题分析：根据图⽰可得：长⽅形的长可以表⽰为x+2y ，长⼜是75厘⽶，故x+2y=75，长⽅形的宽可以表⽰为2x ，或x+3y ，故2x=3y+x ，整理得x=3y ，联⽴两个⽅程得。

初中英语学习材料madeofjingetieji八年级英语Unit 7测试题一．单项选择。

( )1. I ___________about the weather in London tomorrow.A. plan talkingB. will tellC. will talkD. hope to say( )2. In ten hours, they __________in Malaysia.A. areB. will beC. will getD. arrived( )3. After ten hours, they _________in Malaysia.A. gotB. will arriveC. arrivedD. will be( )4. He’s going to play soccer when he ________his homework in an hour.A. will finishB. finishedC. finishesD. is finishing( )5. Kids like studying _________computers.A. onB. atC. inD. for( )6. We should eat _________meat and _________vegetables.A. fewer, moreB. less, fewerC. more, fewerD. less, more( )7. We should spend _________money and _________time playing computer games.A. fewer, fewerB. fewer, lessC. less, lessD. less, fewer( )8. I hope there’ll be ________trees and _________pollution in ten years.A. more, lessB. more, fewerC. less, moreD. fewer, less( )9. We need _________people and _________time to do the work.A. fewer, fewerB. fewer, lessC. less, lessD. less, fewer( )10. ---I think there’ll be less pollution in the future.---_____________. More and more cars will be driven in the future.A. I think soB. I don’t think soC. I agreeD. I hope so( )11. The movie was so ________that we all got _________.A. boring, boringB. boring, boredC. bored, boredD. bored, boring( )12. ---The water in the river is ______.---Yes, water ____is getting more and more serious.A. polluted, pollutedB. pollution, pollutionC. pollution, pollutedD. polluted, pollution( )13. Her homework usually _________two hours.A. takesB. spendsC. paysD. costs( )14. I think it is __________for us to walk on the moon one day.A. possibleB. possiblyC. maybeD. probably( )15. We need to play a part in __________our country more beautiful.A. makeB. makesC. to makeD. making( )16. Trees are __________. We must do something to stop that.A. dangerousB. in dangerousC. dangerD. in danger( )17. ________a reporter, I will meet many interesting people.( )18. Some scientists are trying to make robots _________like humans.A. thinkB. thoughtC. thinkingD. to think( )19. __________the students in our school walk to school every day.A. Nine hundredB. Nine hundredsC. Hundred ofD. Hundreds of( )20. Could you please tell me ____________?A. what will the future likeB. what the future will be likeC. how do you think of the movieD. how you think of the TV play二、完形填空。

英语八年级上一般将来时练习题（Unit6、7）八年级上一般将来时练习题（Unit6、7）1、翻译成英文。

①玛丽要卖她的汽车。

②今天早上我将不吃早餐。

③你打算邀请约翰参加你的聚会吗？④你打算买什么？⑤我下个月打算去北京参观。

⑥她打算长大后搬去上海。

⑦在元月二号将有一场音乐会在我们学校举办。

2. 用正确的形式填空。

1）We are ____________________ (play) basketball tomorrow.2）They __________________ (visit) their aunt next week.3）_____Lucy______________(watch)movie with Lily tomorrow? No, _____ ______. 4）There ___________________________ (be) a football match tomorrow.5）They ___________________ (not practice guitar) next week.3、选择题。

1. Keep practicing and you your English.A. improveB. will improveC. improvedD. were improving2. -I want to know if youhiking with us tomorrow.-If itrain tomorrow, I will.A. will go; will notB. will go; doesn’tC. go; will notD. go; doesn’t3. -Helen, do you know if Martinto my party next week?-I think he will come if hefree.A. will come; will beB. will come; isC. comes; isD. comes; will be4. If Nancythe exam, she will go to Australia for English study.A. passB. passedC. passesD. will pass1、翻译成英文。

牛津译林版八年级上期末复习英语Unit 7 小题练习单选1.It’s time ____ a talk with your son. He didn’t pass the Maths exams.A.f or havingB.for you to haveC.to you to haveD. for you having2.It will be _____ tomorrow and there will be much ______.A.r ainy; windB.rain; windyC.rain; windD.rainy; windy3.What did the weatherman _____ about the weather tomorrow?A.tellB. talkC. sayD. speak4.It rains so _____ that we have to walk very _______.A.heavy; slowB.hard; slowerC. hard; slowlyD. heavy; slowly5.What _____ bad weather it was yesterday! --- Yes, ____ weather was terrible, wasn’t it?A.a; aB./; theC.a; theD. /; a6.--- What about a cup of coffee? You’ll feel better.--- Thanks, I am sleepy. I really need ____.A.oneB.thatC.thisD.it7.In spring, grass, flowers and trees ______ the hill.A.coverB.are covered withC.are coveringD. are covered in8.My younger sister always buys _____ my birthday.A.something awfully forB. a awful present forC.something awful toD.something awful for9. I forgot ____ the door when I left home just now. To my surprise, when I came back, I found it already ______.A.c losing; closedB.to close; closedC.closing; closingD.to close; closing10. They gathered closely together to ______ themselves from the wind.A.preventB.provideC.protectD.prepare11.Robin sings ____ than I, but he doesn’t sing ____ my sister.A.worse; as better asB.worse; as good asC. better; as good asD. better; as well as12. --- Sorry, ______. What do you mean by saying “look out”?--- I asked you “to be careful”, not “to look outside”.A.I can’t hear youB.I can’t hear clearlyC.I don’t notice youD. I don’t follow you13. The temperature tomorrow will be ____ than today. It will stay ____ zero, _____ 2℃.A.higher; above; atB.hot; below; atC.higher; above; toD. high; below; to14.He is ____ interested in English. He often works at it until _____ into the night.A.deep; deeplyB.deep; deepC.deeply; deepD.deeply; deeply15.The children are making _____. How ______ they are playing!A.too much noise; noisilyB.too much noise; noisyC.much too noise; noisyD.much too noisy; noise16. He got out of the car slowly, _____ to the nearest house and telephoned his friend for help.A.walkingB.walkedC. to walkD. walks17. I found _____ hard to tell the differences between the twins Mark and Mike.A.it’sB. itC. itsD. that18. The boy wasn’t ____. As a result, he didn’t pass the exam.A.enough carefulB.enough carefullyC.carefully enoughD. careful enough19. --- I failed my English exam again. I really want to give up.--- Come on. ____ is really over until the moment you stop trying.A.EverythingB.NothingC. AnythingD. None20.Look at the _____ look on their faces. The match must be wonderful.A.boredB. excitingC. excitedD. boring21.The radio says there will be ____ tomorrow. I think it will be _____.A. a bit snow; a bit snowierB. a bit of snowier; a bit of snowC.a bit snowier; a bit ofsnow D.a bit of snow; a bit snowier22.We saw her face ______ a white silk scarf ____ after she heard the teacher’s words.A.covered with; turned redB.was covered with; turn redC.covering; turned redD. covered with; turn red词汇1.Look, what a heavy snow! Maybe it will be even _____(snow) tomorrow.2.--- It _____ heavily last Thursday. There is much ______ this year in Wuxi.--- Yes, it’s much _____ than last year. (rain)3.We usually feel cool and comfortable after heavy ______(阵雨) in summer.4.--- What bad weather! --- Yes, the radio says it will be much ______(wind) tomorrow.5.The woman came in and began to have dinner without ______(introduction) herself.6.It was so quiet that you could hear a pin(针) _______(落下).7.It will be ______(雨) in three hours and there will be much _______(风).8.The weather report says it’s going to be ______(多云) in the afternoon.9.July, August and September are the _______(rain) months of the year in Thailand.10.Can you get someone else to help us finish the ______(剩余的) of the work?11.Do they find out what ______(引起) the big fire?12.I’m afraid you are the _______(noise) in your group. Please be quiet.13.My mother told me that the sun ______(rise) in the east and sets in the west.14.He ________(打赌) 200 yuan on the final score of the match, but failed.15.His _______(突然的) death surprised us all.动词1.--- Thank you for your wonderful treat last night. --- I’m glad you _____(enjoy) yourself.2.She always _______(hide) herself away in her office all day during her stay in Shanghai.3.We should stop all these farmers ______(make) more space for plants and rare birds in nature.4.--- Mary dances best in our school.--- I agree. I’ll never forget _______(see) her dance for the first time.5.The water of the river ______(rise) quickly last year because of the flood.6.--- What do you eat so much ice cream for? --- ______(feel) cool.7.The plane ______(not arrive) here on time because the radio says there will be a heavy snow soon.8.The pianist ______(feel) much better after she _____(take) some medicine just now.9.I think ______(do) the work correctly is more important than to finish it quickly.10.Jerry is a cheerful person. He has nothing ______(worry) about.11.Grace, how can you finish _______(write) the article in such a short time?12.The poor old man sat there alone, ______(watch) the children play football.13.When ________(enter) the classroom, I saw a wallet ______(lie) on the floor.14.A strong wind _______(blow) away all the clouds in the sky. It becomes clear now.15.We didn’t see snow for years because the temperature always ______(stay) above zero.16.I have to go now. Someone _____(wait) for me at the school gate.17.About 40 per cent of the students now in this school ______(come) from Shanghai.18.I stopped ______(listen), but heard nothing.19.Jessica may no more _______ (prevent) his son from meeting his friends.20.The news says that the number of Coronavirus people ________(not drop) at the end of this year in the USA.完成句子1.穿上这条棉质的短裙你会觉得凉爽。

Test for Unit 7一英汉互译1. 活到200岁2. 在未来3. 住在公寓里4. 寻找5. 在太空站6. 在太空7. 似乎不可能8. 人类的仆人 9. 像人类一样思考10 污染环境 11. 单词的意思12. another foreign language 13. move to other planets. 搬到其他的星球去14. in danger ，脱离危险20. 在某一点上；在某种程度上；在某个时候二、完形填空(共15小题；每小题1分，满分15分)阅读下面短文，掌握大意，然后从各题所给的四个选项中选出最佳选项。

What will life be like in 2050？Will life be better，__16__or the same as now？I often think about the __17__.I believe life will probably be very __18__in 2050.First，I think there will be __19__televisions in 2050.People will watch __20__programs on the Internet，__21__they won't need TVs.I believe __22__will be as cheap as telephones.Most people will have __23__money to own their personal computers.For transportation，cars will run on clean fuels，so there will be less __24__.By 2050，cars will have computers to control how __25__they puters will __26__cars to any place you want to go.There will be __27__accidents.We won't need so many __28__.Now you can see robots in many factories.Factories __29__robots，because they do not ask for money.__30__2050，robots will work everywhere in schools，offices and homes.( )16.A.worse B．worst C．good D．best( )17.A.life B．prediction C．picture D．future( )18.A.similar B．easy C．different D．difficult( )19.A.no B．enough C．many D．more( )20.A.kind of B．a kind of C．all kinds of D．kind( )21.A.but B．so C．or D．until( )22.A.books B．letters C．e­mails D．computers( )23.A.less B．enough C．more D．foreign( )24.A.work B．water C．space D．pollution( )25.A.quickly B．soon C．long D．often( )26.A.drive B．ask C．find D．hope( )27.A.less B．much C．many D．few( )28.A.teachers B．policemen C．cars D．fuels( )29.A.know B．hear C．use D．sell( )30.A.By B．Before C．After D．For三、阅读理解(共15小题；每小题2分，满分30分)阅读下列材料，从每题所给的A、B、C、D四个选项中选出最佳选项。

新目标八年级上册英语Unit 7 Section B (3a-Self Check)练习题及答案二Part1( )1．It's reported that people throw ________ plastic bags along this street every day.A．hundred B．hundredsC．hundred of D．hundreds of( )2．Look! There are some birds ________ in the sky. They are very beautiful.A．to fly B．fly C．flying D．flown( )3．They usually go shopping ________ their lunch break.A．against B．among C．between D．during( )4．Teachers shouldn't ask students to copy the words ________.It's simple and boring.A．much again B．once again overC．over and over again D．again over and over( )5．It is ________ a beautiful garden ________ we like to play in it.A．so; that B．such; thatC．too; to D．very; that( )6．I ________believe everything ________ be free in 20 years.A．/；won't B．don't；won'tC．don't；will D．will；doesn't( )7．The Internet makes it ________ for us to send information toeach other in a few seconds.A．possible B．necessaryC．impossible D．important( )8．—Where is Anna?—She ________ still at work.A．maybe B．probably C．perhaps D．may be( )9．He will ________come tomorrow.A．perhaps B．maybe C．probably D．may be( )10．—I'll have a tennis game tomorrow. I'm a little bit nervous.—Believe in ________. You're the best in our club.A．yourself B．myselfC．herself D．himself( )11．—Math is too difficult. I nearly give it up.—Please don't. Nothing is________ if you put your heart into it.A．important B．impossibleC．interesting D．possible( )12．It's ________ to drive your car too fast.A．dangerous B．carefulC．different D．hungry( )13．Will there be any paper money ________ 100 years?A．with B．on C．at D．in( )14．Yesterday________ people came to the town to watch the carrace.A．hundreds B．hundredC．hundreds of D．hundred of( )15．I agree ________ you.I think you are right.A．to B．on C．of D．with( )16．—It's cold today.I can't stand it.I hope tomorrow won't be so ________．—I can't, either.But the radio says it will be even ________tomorrow.A．cold; cold B．cold; colderC．colder; colder D．colder; coldest( )17.—________will the invitations be sent to our guests?—In three days.A．How often B．How soonC．How long D．How far( )18．If I have enough money, I________ a school bus to help the poor children go to school.A．buy B．boughtC．will buy D．am buying( )19．Lily________ her shoes, but she didn't________ them.A．looked for; find B．found; looked forC．looked; find out D．found out; looked for( )20．Many tall buildings ________ and over 80 people were inside on December 23, 2015.A．fell down B．fell behindC．fell over D．fell off( )21．We'll ______move to new apartments very soon!A．can B．couldC．be able D．be able to( )22．—Will people live to be 200 years old?—______.They can't live so long.A．Yes，they do B．No，they don'tC．No，they won't D．Yes，they will( )23．In five years，Sally ______ a basketball player.A．was B．isC．will be D．will( )24．It seems to me that Lucy and Lily______your classmates.A．is B．areC．has D．have( )25．—I think math is more useful than P．E.—I don't______you.They are both A．get on with B．catch up withC．talk with D．agree with( )26．Tom will ________ go to France on vacation this summer.A．possible B．impossible C．probable D．probably( )27．She likes ________ nice skirts on weekends.A．wearing B．wear C．putting on D．put on( )28．My brother will be a doctor ________ two months.A．at B．in C．on D．to( )29．Alice is as ________ as Lucy in the class.A．tall B．tallerC．tallest D．the taller( )30．What will the weather be ________ tomorrow?A．of B．onC．in D．like( )31．We must do something so that there will be ________ pollution in our city.A．few B．lessC．fewer D．many( )32．There ________ a basketball game this afternoon.A．have B．is going to beC．has D．is going to have( )33.—Is there ________ apartment in the neighborhood?—Yes.Mr.Wang lives in ________ apartment.A．an；an B．a；a C．an；the D．the；the( )34.—What's the ________ of the gift?—It's round.A．shape B．price C．size D．space( )35.—What did you do ________ your summer holiday，Anna?—I went to visit my grandparents in the countryside.A．for B．into C．during D．inside( )36.—Tell kids not to play with fire.It's pretty ________.—OK.I'll do it.A．meaningless B．carefulC．easy D．dangerous( )37.When we arrived there，it was ________ ten o'clock.So we were late.A．still B．already C．even D．yet( )38.—Jim，don't run in the hallways.—Sorry，I ________ do that again.A．should B．must C．couldn't D．won't( )39.—The Great Wall is very famous.—Yes，________ people come to visit it every day.A．hundred B．hundredsC．hundred of D．hundreds of( )40.We will have ________ free time because the robots will work for us.A．less B．more C．fewer D．most( )41.—________ will your mother come back?—In two days.A．How soon B．How manyC．How long D．How often( )42.You will ________ take a holiday after the test.A．can B．could C．be able to D．are able to( )43.—What are you doing，Jenny?—Oh，I'm ________ my keys.I can't remember where I put them. A．waiting for B．writing downC．making up D．looking for( )44.It is very dangerous for you ________ soccer in the street. A．play B．to play C．playing D．to playing( )45.—They ________ a lot of trees on the mountain.—Yes，but a bad person cut them down.A．planted B．plantC．are planting D．will plant( )46.—________ a new film next week.—Really？I will go to watch it.A．There is B．There will haveC．There will be D．There is going to have( )47.—Maybe we will live on another planet.—________.The earth is our only home.A．I agree B．I hope soC．I don't think so D．You're right( )48.Wang Yaping is ________ Chinese astronaut.I want to be ________ astronaut like her.A．a；the B．an；theC．an；a D．a；an( )49.There are many workers in the paper ________.A．planet B．wordC．college D．factory( )50.I don't agree ________ you.I think she has something to do ________ it.A．to；about B．with；withC．with；to D．to；about( )51.The college is so famous that ________ people come and visit it every term.A．hundreds of B．hundredC．hundred of D．hundreds( )52.—Do you ________ what he said?—No，he is always making up stories.A．promise B．improveC．believe D．choose( )53.Look！There are a lot of kids ________ games in the park.A．play B．playingC．to play D．plays( )54.—Will Jane appear at the party tonight?—________.She is already on the way.A．Yes，she will B．Yes，she isC．No，she isn't D．No，she won't( )55.It's ________ to remember all the names in a few minutes.It's too difficult.A．simple B．possibleC．lucky D．impossible( )56.I lost my new watch yesterday.I ________ it everywhere，but I couldn't ________ it.A．found；findB．found；look forC．looked for；findD．looked for；look for( )57.________ a basketball match next Wednesday?A．Will haveB．Will beC．Will there beD．Will there have( )58.—Where is Mary，Kate?—She ________ went shopping with her parents.A．maybe B．possibleC．probably D．probable( )59.He works at night and sleeps ________ the day.A．during B．atC．for D．with( )60.Guilin is a beautiful place.________ people visit it every day.A．Hundred B．HundredsC．Hundreds of D．Hundred of( )61.Hank lost his job two months ago. He is now ________ a new job.A．looking out B．looking afterC．looking for D．looking up( )62.People never know what ________ in 100 years.A．happen B．will happenC．happened D．will be happenedPart2按要求完成句子，每空一词。

人教新目标英语八年级上册Unit 7 Will people have robots?词句精讲精练词汇精讲1. duringduring是介词，意为“在……期间”。

例如：I went to see my uncle during my stay in Beijing. 我在北京逗留期间去北京看我叔叔了。

【拓展】during；in与for(1) during指“在……时间内，在……的期间”。

谓语动词常为表示持续性的动作或状态的动词，时间段前常有限定词（the; 物主代词等），表特指。

例如：He asked many questions during the three meetings. 在这三次会议期间，他问了许多问题。

(2) in意为“在……时间内”，一般情况下可以和during互换，用in时往往强调某一动作发生在某一时间段中的某一时间点；during既可表示“在整个时间段期间”，也可表示“某时间段内的某个时间点”。

例如：Mike put his hand up three times during/in the class. 在这节课内，Mike举了三次手。

(3) for意为“（时间）长达……”，强调时间由始至终，动作也贯穿这段时间的始终，可以和完成时连用。

强调持续时间的长短，回答how long的提问；而during则是指动作所发生的时间，回答when的提问。

例如：He stayed in Beijing for two years. 他在北京住了两年。

He swims every day during the summer. 夏天他每天去游泳。

2. in 100 yearsin 100 years意为“100年之后”，是由“介词in + 一段时间”构成，表示“在……之后”，多用于一般将来时。

对此短语提问时常用how soon。

例如：I will finish the task in two hours. 我将在两个小时后完成这项任务。

北师大版八年级数学上册第七章《3.平行线的判定》课时练习题（含答案）一、选择题1．如图，直线a 、b 被直线c 所截．若∠1=55°，则∠2的度数是（ ）时能判定a ∥b ．A ．35°B ．45°C ．125°D ．145° 2．如图，给下列四个条件：①12∠=∠；②3=4∠∠；③5B ∠=∠；④180B BAD ∠+∠=°．其中能使//AB CD 的共有（ ）A ．1个B ．2个C ．3个D ．4个 3．如图，直线a b ，且直线a ，b 被直线c ，d 所截，则下列条件不能．．判定直线c d ∥的是（ ）A ．3=4∠∠B ．15180∠+∠=︒C ．12∠=∠D ．14∠=∠4．如图，下列条件中，能判断直线a ∥b 的有（ ）个．①∠1＝∠4；②∠3＝∠5；③∠2+∠5＝180°；④∠2+∠4＝180°A ．1B ．2C ．3D ．45．如图，要使AD BC ∥，则需要添加的条件是（ ）A ．A CBE ∠=∠B ．AC ∠=∠ C ．C CBE ∠=∠D ．180A D ︒∠+∠= 6．如图，把一副直角三角板如图那样摆放在平行直线AB ，CD 之间，∠EFG ＝30°，∠MNP ＝45°．则：①EG PM ∥；②∠AEG ＝45°；③∠BEF ＝75°；④∠CMP ＝∠EFN ．其中正确的个数是（ ）A ．1B ．2C ．3D ．47．如图，在下列条件中，不能判定直线a 与b 平行的是（ ）A ．∠1=∠2B ．∠2=∠3C ．∠3=∠5D ．∠3+∠4=180°8．下面是投影屏上出示的抢答题，需要回答横线上符号代表的内容．则回答正确的是（ ）A．◎代表∠FEC B．@代表同位角C．▲代表∠EFC D．※代表AB二、填空题9．如图，请填写一个条件，使结论成立：∵__________，∴//a b．10．如图，直线a、b被直线c所截，现给出的下列四个条件：①∠4=∠7；②∠2=∠5；③∠2+∠3=180°；④∠2=∠7．其中能判定a∥b的条件的序号是____________________11．已知三条不同的直线a、b、c在同一平面内，下列四条命题：①如果a∥b，a⊥c，那么b⊥c；②如果b∥a，c∥a，那么b∥c；③如果b⊥a，c⊥a，那么b⊥c；④如果b⊥a，c⊥a，那么b∥c．其中假命题的是___．（填写序号）12．如图，点E是CD上的一点，Rt△ACD≌Rt△EBC，则下结论：①AC＝BC，②AD∥BE，③∠ACB＝90°，④AD+DE＝BE，成立的有_____个．13．如图，点E是AD延长线上一点，如果添加一个条件，使BC∥AD，则可添加的条件为__________．（任意添加一个符合题意的条件即可）14．一副三角板按如图所示叠放在一起，其中点B 、D 重合，若固定三角形AOB ，改变三角板ACD 的位置（其中A 点位置始终不变），下列条件①∠BAD ＝30°；②∠BAD ＝60°；③∠BAD ＝120°；④∠BAD ＝150°中，能得到的CD ∥AB 的有__________．（填序号）三、解答题15．如图，利用尺规，在ABC 的边AC 上方作CAE ACB ∠=∠，若AB BC ⊥，证明：AB AE ⊥（尺规作图要求保留作图痕迹，不写作法）．16．如图,已知∠1=∠3,AC 平分∠DAB ,你能推断出哪两条直线平行?请说明理由.17．如图，已知∠1＝∠2，∠3+∠4＝180°，请说明AB //EF 的理由．18．如图，已知AGF ABC ∠=∠，12180∠+∠=︒．（1）试判断BF 与DE 的位置关系，并说明理由；（2）若BF AC ⊥，2140∠=︒，求AFG ∠的度数．19．如图，在ABC 中，90C ∠=︒，顶点B 在直线PQ 上，顶点A 在直线MN 上，BC 平分PBA ∠，AC 平分MAB ∠．(1)求证：PQ //MN ；(2)求QBC NAC ∠+∠的度数．20．已知：如图，A、F、C、D在同一直线上，AB∥DE，AB＝DE，AF＝CD，求证：(1)BC＝EF；(2)BC∥EF参考答案1．C2．B3．C4．C5．A6．C7．C8．C9．∠1=∠4（答案不唯一）10．①④11．③12．113．∠A+∠ABC=180°或∠C+∠ADC=180°或∠CBD=∠ADB或∠C=∠CDE．（答案不唯一）14．①④．15．解：如图，证明：∠CAE= ∠ACB，∥，BC AE180∴∠+∠=︒，EAB B⊥，即90AB BCB，∴∠=︒-∠=︒-︒=︒，EAB B1801809090∴⊥．AB AE16．解：可以推断出DC∥AB，理由如下：∵AC平分∠DAB，∴∠1=∠2(角平分线的定义)，又∵∠1=∠3，∴∠2=∠3(等量代换)，∴DC∥AB(内错角相等，两直线平行). 17．解：12∠∠＝，AB CD∴，//∠+∠︒＝，34180∴，CD EF//∴．AB EF//BF DE，18．解：()1//理由如下：AGF ABC∠=∠，∴，GF BC//∴∠=∠，13∠+∠=︒，1218032180∴∠+∠=︒，∴；//BF DE()2//BF DE，BF AC⊥，DE AC∴⊥，∠=︒，12180∠+∠=︒，2140∴∠=︒，140∴∠=︒-︒=︒．904050AFG19（1）证明：∵BC 平分PBA ∠，∴2PBA ABC ∠=∠，∵AC 平分MAB ∠，∴2MAB CAB ∠=∠，∵90C ∠=︒，∴90ABC CAB ∠+∠=︒，∴∠P AB +∠MAB =2∠ABC +2∠CAB =2(∠ABC +∠CAB )=2×90°=180°， ∴PQ MN ∥；（2）解：由（1）知：PQ MN ∥，∴180ABQ NAB ∠+∠=︒，∵90C ∠=︒，∴90ABC CAB ∠+∠=︒，∴18090270QBC NAC ABQ NAB ABC CAB ∠+∠=∠+∠+∠+∠=︒+︒=︒．20．（1）证明：（1）//AB DE ，A D ∴∠∠＝，AF CD ＝，AC DF ∴＝，在ABC 与DEF 中AB DE A D AC DF =⎧⎪∠=∠⎨⎪=⎩，ABC DEF SAS ∴≅（）， BC EF ∴＝．（2）（2）ABC DEF ≅，BCA EFD ∴∠∠＝ ，//BC EF ∴ ．。